1. Field of Invention
Bite impression trays.
2. Description of the Prior Art
This invention relates to a bite tray which is an improvement on the structures disclosed in my United States Letters Pat. No. 2,713,202 of July 19, 1955, No. 3,822,473 of July 9, 1974, and in my copending application Ser. No. 460,430, filed Apr. 12, 1974, and entitled Bib and Combination Thereof With Bite Tray, now U.S. Pat. No. 3,903,602, of Sept. 9, 1975. More particularly my invention is an improvement in the frame of the bite tray disclosed in my above identified patents and its interrelation with the bib of my above copending application.
As described in my U.S. Pat. No. 3,822,473, two bite tray frames are disclosed, each being in the form of a single length of stiff, resilient wire bent to provide a buccal side frame member, a lingual side frame member spaced laterally therefrom, and an intermediate or rear frame member of which the opposite ends connect with the rear ends of the buccal frame member and the lingual frame member, respectively. A portion of the wire extends endwise beyond the opposite or forward end of the buccal frame member and provides a handle. The opposite or forward end of the lingual frame member is left free and unconnected in any way to the buccal frame member.
Companion or mating tabs are provided on the outer end portions of the handles, respectively, of the two frames. The tabs are interfitted and connected so that they support the handles for swinging toward and away from each other in a common plane and for bodily movement transversely relative to each other in that plane so that the frame can be adjusted for different sizes and shapes of dental arches. The interfitting tabs can be clamped together in the adjusted positions and, when so clamped, can be held readily between the thumb and forefinger for introducing into a patient's mouth.
Each frame carries a bib. Each bib is provided at its lateral margins with channel members which are adapted for snap fastening engagement with the buccal frame member and the lingual frame member, respectively, of an associated frame, so as to hold the bib in bridging relation to the space between the buccal and lingual frame members and for sliding of the channels of the bib lengthwise of their associated buccal and lingual frame members to different adjusted positions lengthwise of the lingual and buccal frame members, in which positions they are retained by frictional binding.
The channel members are sufficiently rigid so that insofar as they may extend beyond the free ends of the lingual frame members their overhanging portions are adequate to be self-supporting and to support the overhanging portion of the bib with the necessary quantity of impression paste thereon.
The adjustment of the tray to fit different dental arches of which a bite registration impression is to be taken proceeds by trial and error. When adjusted for the particular arches, and with bibs is place and supporting proper charges of impression paste, the frame is inserted in the open mouth in a position to take the bite registration impression.
The relation of the buccal and lingual frame members of each of the above frames to each other and their relation, in turn, to their associated handles, limited substantially the possibilities of placement of the frames in those optimum forward positions in the mouth desirable in those cases in which the rearmost upper and lower posterior teeth, or two or three occluding teeth forwardly therefrom are missing. In such instances, the number of registration impressions of occluding teeth is very limited, and yet it is desirable that as many occluding teeth as possible be included in the bite registration impression so that the castings of dental impressions to be used for partial or full dental plates can be mounted in proper or true centric occlusion in the articulator in which the impressions are mounted and adjusted subsequently for constructing proper dentures. With the previous frames, the lengths of the lingual frame member of each frame is so long relative to the buccal frame member that the lingual frame member would strike the interior of the dental arch at the lingual surface of the labial teeth upon slight movement of the frame to desirable more forward adjusted positions. Furthermore, the handles were of such length relative to the buccal and lingual frame members that it was difficult for the dentist to hold the frame and bibs substantially coplanar with the occusion plane of the teeth while he held the jaws in true centric relation for centric occlusion.